One Register, Slowly Diffusing: A Topic-Model, Vector-Database and Graph-Theoretic Reading of the Beatles' Lyrical Evolution (1965–1969)
Abstract This study traces the lyrical evolution of the Beatles across four albums — Rubber Soul (1965), Revolver (1966), Sgt. Pepper’s Lonely Hearts Club Band (1967) and Abbey Road (1969) — using a pipeline of LLM-driven topic modeling (BERTopic), a vector database (OpenAI text-embedding-3-large indexed in ChromaDB), embedding geometry, and graph theory. The study puts a falsifiable question to the canonical critical narrative — that the Beatles moved through four discrete stylistic eras — by testing whether the albums occupy separable territories in lyrical-semantic space. ...